content: Re-enable ChildDiscardableSharedMemoryManagerBrowserTest.LockMemory test.

content/child/child_discardable_shared_memory_manager_browsertest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/discardable_memory.h"
 #include "content/child/child_discardable_shared_memory_manager.h"
 #include "content/child/child_thread_impl.h"
 #include "content/common/host_discardable_shared_memory_manager.h"
@@ skipping 31 matching lines @@
   }
 
   static void UnlockMemory(base::DiscardableMemory* memory) {
     memory->Unlock();
   }
 
   static void FreeMemory(scoped_ptr<base::DiscardableMemory> memory) {}
 };
 
 IN_PROC_BROWSER_TEST_F(ChildDiscardableSharedMemoryManagerBrowserTest,
-                       DISABLED_LockMemory) {
+                       LockMemory) {
   const size_t kSize = 1024 * 1024;  // 1MiB.
 
   NavigateToURL(shell(), GURL(url::kAboutBlankURL));
 
   scoped_ptr<base::DiscardableMemory> memory;
   PostTaskToInProcessRendererAndWait(base::Bind(
       &ChildDiscardableSharedMemoryManagerBrowserTest::AllocateLockedMemory,
       kSize, &memory));
 
   ASSERT_TRUE(memory);
@@ skipping 68 matching lines @@
             kSize);
 
   PostTaskToInProcessRendererAndWait(base::Bind(
       &ChildDiscardableSharedMemoryManagerBrowserTest::ReleaseFreeMemory));
 
   EXPECT_EQ(HostDiscardableSharedMemoryManager::current()->GetBytesAllocated(),
             0u);
 }
 
 }  // content